[HWYSTR455]

My understanding is, technically, the variance of tolerances is the mount pad of the block, and potentially effected by the line bore.

It can also be impacted by flywheel/flexplate runout.

The pads on the mini starter are generally CNC cut, so doubtful they vary too much.

I just did mine recently, and the pad of the mini starter was wider than the pad on the block, and had to bevel the edge because it was making contact with the trans bell, and not seating properly. That is a Summit mini, before anyone asks.

Usually, once you've determined the stack of shims you need, you never have to do it again, just reuse the same stack on any/every starter you bolt up. (which further supports the block factor)

Ask the guys who have tried to shotgun it by mounting and testing shims in use who are using IMI mini starters, see what they say. The drive gear on the starter is considered 'sacrificial', to save the ring gear, because it's much easier to swap a starter than one of those. And the IMI gears are softer than most, or is what I have found. Others too, apparently.

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